Good lord! I messed around with it last night until I got to level 13 and my husband got mad at me for sitting here like a zombie. So I left it open and here I sit again. Only 4 more to go. It's so addictive.
addictive... when finally coming up for air my eyes are all blurry. I must not have been blinking much while so engrossed. Nice learning curve where you discover the little tricks along the way like finding the points with the most and least connecting lines first.